Lasing of ambient air with microjoule pulse energy pumped by a multi terawatt IR femtosecond laser

Abstract

We report on the lasing action of atmospheric air pumped by an 800 nm femtosecond laser pulse with peak power up to 4 TW. Lasing emission at 428 nm increases rapidly over a small range of pump laser power, followed by saturation above ~ 1.5 TW. The maximum lasing pulse energy is measured to be 2.6 uJ corresponding to an emission power in the MW range, while a maximum conversion efficiency of is measured at moderate pump pulse energy. The optical gain inside the filament plasma is estimated to be excess of 0.7/cm. The lasing emission shows a doughnut profile, reflecting the spatial distribution of the pump-generated white-light continuum that acts as a seed for the lasing. We attribute the pronounced saturation to the defocusing of the seed in the plasma amplifying region and to the saturation of the seed intensity.

References in corpus (2)

• Self-seeded lasing in ionized air pumped by 800 nm femtosecond laser pulses
• Self-induced white-light seeding laser in a femtosecond laser filament

Cited by in corpus (9)

• Population Redistribution among Multiple Electronic States of Molecular Nitrogen Ions in Strong Laser Fields
• Recollision induced superradiance of ionized nitrogen molecules
• Backward stimulated radiation from filaments in Nitrogen gas and air pumped by circularly polarized 800 nm femtosecond laser pulses
• Superfilamentation in air
• Gain dynamics of a free-space nitrogen laser pumped by circularly polarized femtosecond laser pulses
• Impulsive rotational Raman scattering of N2 by a remote "air laser" in femtosecond laser filament
• Amplification of intense light fields by nearly free electrons
• Two-color interferometer for the study of laser filamentation triggered electric discharges in air
• Ramsey interferometry through coherent $X^2{\Sigma }_g^{+}-A^2{\Pi }_u-B^2{\Sigma }_u^{+}$ coupling and population transfer in N${}_2^{+}$ air laser